feat(clients): Wake-on-LAN in apple/linux/windows/android/decky

Each client learns a host's MAC from the mDNS `mac` TXT while it's awake, persists it on the saved-host record, and — when reconnecting to an offline host — sends a magic packet before connecting, plus an explicit "Wake host" action. Apple wraps the C-ABI; linux/windows call the core fn directly (linux also gains a --wake CLI mode); android via a new nativeWakeOnLan JNI export (the mDNS browse record gains a 7th mac field); decky shells out to the linux client's --wake before launching the stream.

iOS/tvOS need the managed com.apple.developer.networking.multicast entitlement (pending Apple approval), so the wake path + UI are gated off via PunktfunkConnection.wakeOnLANAvailable and the entitlement is commented out — keeping iOS/tvOS releasable. MAC-learning stays active on every platform so it lights up the moment it's ungated. macOS works today.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

clients/decky/src/backend.ts

@@ -122,6 +122,12 @@ export const setSettings = callable<[settings: StreamSettings], { ok: boolean }>
   "set_settings",
 );
 export const killStream = callable<[], { ok: boolean }>("kill_stream");
+// Send a Wake-on-LAN magic packet to a saved host (headless flatpak --wake) so a sleeping host is
+// up by the time the stream connects. The MAC is looked up from the flatpak client's own
+// known-hosts store; `ok: false` (no-op) when none has been learned yet. Fire before launching.
+export const wake = callable<[host: string, port: number], { ok: boolean; error?: string }>(
+  "wake",
+);
 export const checkUpdate = callable<[force: boolean], UpdateInfo>("check_update");
 // Update the flatpak client in the user installation (`flatpak update --user -y io.unom.Punktfunk`).
 export const updateClient = callable<

clients/decky/src/steam.ts

@@ -8,7 +8,7 @@
 // and start it with RunGame. The wrapper then execs
 // `flatpak run io.unom.Punktfunk --connect <host>` as a reaper descendant.
 
-import { runnerInfo, shortcutArt } from "./backend";
+import { runnerInfo, shortcutArt, wake } from "./backend";
 
 // SteamClient is a Steam-internal global injected into the CEF context; it is not fully typed
 // by @decky/ui, so declare the surface we use. Signatures verified against MoonDeck + the
@@ -219,6 +219,11 @@ export async function launchStream(
   port: number,
   opts: LaunchOpts = {},
 ): Promise<void> {
+  // Wake-on-LAN: if this host is asleep, nudge it awake before the stream connects. Kicked off now
+  // so it races with the shortcut setup (near-zero added latency), and awaited just before RunGame.
+  // Best-effort — the flatpak client's --wake looks up the host's learned MAC (a no-op if none is
+  // known), and the connect that follows has its own retry window, so a failure never blocks launch.
+  const waking = wake(host, port).catch(() => ({ ok: false }));
   const { appId, runner } = await ensureShortcut();
   // Best-effort so the Deck's rich controls reach the client; no-op if the API is absent (the user
   // disables Steam Input manually — see the Settings instruction).
@@ -240,6 +245,7 @@ export async function launchStream(
   // KEY=value ... %command% args — %command% expands to the shortcut exe (/bin/sh); the wrapper
   // script rides behind it as an argument and reads PF_* from the environment.
   SteamClient.Apps.SetAppLaunchOptions(appId, `${env.join(" ")} %command% "${runner}"`);
+  await waking; // ensure the magic packet is out before the connect attempt
   SteamClient.Apps.RunGame(gameIdFromAppId(appId), "", -1, 100);
 }